1. Field of the Invention
The field of the invention is a high energy feed supplement for use in the raising of cattle, horses, sheep and other livestock.
2. Description of the Prior Art
Feed supplements are generally made from molasses and other nutrients and are generally manufactured in the form of either a liquid feed supplement, or a solid block supplement known as a feed block. The present invention is directed to an improved feed block and the novel method and apparatus for making such a feed block.
A feed block is desirable in that when used to supplement an animal""s diet, the animal""s productivity can be improved significantly. Productivity includes factors such as weight gain, lactation and reproduction. A feed block also improves the animal""s efficiency in digesting the forages that constitute the bulk of its diet. U.S. Pat. No. 3,961,081 to McKenzie and U.S. Pat. No. 4,749,578 to Benton and Patrick disclose prior art feed blocks and the methods and apparatus for making them. These patents are incorporated herein by reference. The present invention relates to a novel method for making an improved feed block.
The McKenzie patent teaches a method of making a feed block which is intended to be non-porous, hard and vitreous. A fluid feed mixture of molasses and other nutrients is heated at ambient pressure to between about 225xc2x0 F. and about 300xc2x0 F. to remove the bulk of the water from the mixture. The partially dehydrated mixture is then subjected to a vacuum without additional heating to further dehydrate the mixture. This two-step process was necessary to promote a high degree of dehydration without causing foaming of the mixture. The fully dehydrated mixture is then formed into the desired shape and cooled to produce a feed block.
While the McKenzie patent represented a significant improvement in the area of feed block manufacturing, its shortcomings led to the development of the Benton-Patrick feed block and method for making feed block as disclosed in the Benton-Patrick patent. One such shortcoming that the Benton-Patrick invention overcame is that the blocks produced by the method of the McKenzie patent tend to be porous and hygroscopic, causing them to absorb atmospheric moisture. Once the McKenzie blocks absorb moisture, they soften and become sticky making them difficult to handle and causing a loss of consumption control.
The feed blocks of the Benton-Patrick patent are an improvement over the McKenzie blocks. The Benton-Patrick blocks are water resistant, non-porous, hard, and vitreous feed blocks that do not tend to soften or become sticky when exposed to atmospheric moisture. By the method of the Benton-Patrick patent, a mixture of molasses and about 1% to about 2% by weight of insoluble soap are first heated at ambient pressure to between about 225xc2x0 F. and 300xc2x0 F. to drive off most of the water present. The partially dehydrated mixture is subjected to a vacuum to drive of f most of the remaining water in the mixture. The fully dehydrated mixture is then formed into feed blocks and allowed to harden. Other nutrients can also be added to the molasses and soap mixture prior to the heating step, and/or to the dehydrated mixture prior to forming it into blocks. The improved properties of the Benton-Patrick feed block are attributed to the initial addition of insoluble soap which provides the improved water resistant characteristics for the feed block produced.
Despite the improved water resistant characteristics of the Benton-Patrick feed block, even it has certain shortcomings. It is well known that when sugars such as those found in molasses are subjected to heat, some degradation of the sugars occurs. Thermal degradation can also be expected when other nutrients such as proteins, fats, carbohydrates and vitamins are subjected to heat. In producing feed block by prior art methods, a significant portion of the nutritional value of the ingredients that make up the feed block is destroyed by the formation of reaction products that are often indigestible to the animals that eat the feed block. One such thermal degradation reaction that destroys carbohydrates is known as the Maillard reaction. This particular reaction involves the chemical reaction of carbohydrates with amino acids and water to form a generally indigestible polymer. The Maillard reaction is particularly undesirable in the production of feed block.
Heat and moisture are known to increase the rate of these degradation reactions. An improved feed block and a method and apparatus for making such a feed block are desired where the loss of nutrients by thermal degradation is reduced.
Vacuum dehydration of molasses is also generally known in the prior art, but has typically been avoided due to foaming and swelling of the molasses which make its handling extremely difficult.
The present invention provides an improved feed block with a higher proportion of nutrients than are contained in prior art feed blocks. The improved feed block is produced by a novel process and apparatus in which the ingredients for the feed block are dehydrated at low temperature and pressure in order to avoid the undesirable thermal degradation reactions which are responsible for the destruction of a portion of the nutrients in prior art feed blocks. By careful control of process conditions which include time, temperature, pH, and degree of dehydration, the disadvantages of prior art dehydration processes can also be avoided.
In the novel process and the novel production apparatus, a fluid mixture comprising molasses and other nutrients and additives is fed into a dehydration vessel. The dehydration vessel operates at a partial vacuum and includes an internal mixer and an external recycle pump both of which help to agitate the fluid mixture. A heating section in a lower portion of the dehydration vessel is used to heat the fluid mixture to a temperature that is preferably less than about 130xc2x0 F. in order to drive the water from the fluid mixture. A cooling section in an upper portion of the dehydration vessel is used to condense the water vapor driven from the fluid mixture by the heating section. The condensed water is collected in a drip pan and flows to a condensate collector where the amount of condensate can be measured to determine the degree to which the fluid mixture has been dehydrated. As the fluid mixture is dehydrated, the rates of the Maillard and other thermal degradation reactions slow. Once the desired degree of dehydration has been achieved, the dehydrated mixture is removed from the dehydration vessel so that it can be formed into block shapes and cooled.